SYSTEM AND PROGRAM PRODUCT TO RECOVER FROM NODE FAILURE/RECOVERY INCIDENTS IN DISTRIBUTED SYSTEMS IN WHICH NOTIFICATION DOES NOT OCCUR

• US 20080225702A1
• Filed: 05/23/2008
• Published: 09/18/2008
• Est. Priority Date: 01/27/2003
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Blackmore, Robert S., Kim, Chulho, Sivaram, Rajeev, Epter, Scott D., Chen, Amy X.
• Granted Patent: US 8,116,210 B2
• Time in Patent Office: Days
• US Class Current: 370/221
• CPC Class Codes: B60R 25/1003 Alarm systems characterised by arm or disarm features

Abstract

Epoch numbers are maintained in a pair wise fashion at a plurality of communication endpoints to provide communication consistency and recovery from a range of failure conditions including total or partial node failure and subsequent recovery. Once an epoch state inconsistency is recognized, negotiation procedures provide an effective mechanism to reestablish valid communication links without the need to employ global variables which inherently possess greater transmission and overhead requirements needed to maintain communications. Renegotiation of recognizably valid epoch numbers occurs on a pair wise basis.

Claims

1. A computer readable medium having computer executable instructions causing a computer to maintain at each one of a plurality of communication endpoints in a distributed data processing system, pair wise epoch indications relative to other ones of said plurality of communication endpoints and negotiate message transmission between pairs of said endpoints based on said pair wise epoch indications.

2. A distributed data processing system having a plurality of nodes containing executable instructions, in memory locations within the nodes of said distributed data processing system, for causing nodes in said distributed data processing system to maintain at each one of a plurality of said nodes in said distributed data processing system, pair wise epoch indications relative to other ones of said plurality of nodes in said distributed data processing system and for causing said nodes in said distributed data processing system to negotiate message transmission between pairs of said nodes in said distributed data processing system based on said pair wise epoch indications.